Shift control for auxiliary transmissions



Oct. 6, 1953 c. M. PERKINS 2,654,268

SHIFT CONTROL FOR AUXILIAFY TRANSMISSIONS Filed July 14, 1951 s sheets-sheet 1 /aa q /33 V @Afm W @E fw Aux/Mey 50x INVENTOR. @man M Daw/NJ 061:. 6, 1953 '0, M PERK|NS 2,654,268

SHIFT CONTROL FoR AUXILIARY TRANsMssIoNs Filed July 14, 1951 s sheets-sheet 2 1 nventor (ff/aaa.: /Vex//VJ Oct. 6, 1953 c. M. PERKINS 2,654,258

SHIFT CONTROL FOR AUXILIARY TRANSMISSIONS Filed July 14, 1951 3 Sheets-Sheet 5 (ff/afs /FZ Pff/mas Patented Oct. 6, 1953 SHIFT CONTROL FOR AUXILIARY TRANSMISSIONS Charles M. Perkins, Kalamazoo, Mich., assgnor to Fuller Manufacturin tion of Delaware g Company, a corpora- Application July 14, 1951, Serial No. 236,817

9 Claims. (Cl. 774-4745) This invention relates in general to a device for controlling and effecting the shift of an auxiliary transmission in response to a predetermined movement in a main transmission associated therewith, and more particularly to such a device which is actuable by the interlock mechanism of the gear shift on the main transmission and which is arranged to effect shifting of said auxiliary transmission upon the arrival of said main transmission into neutral position.

In the application of Ludvigsen and Backus, Serial No. 133,404, a transmission assembly was disclosed comprising a main gear group and an auxiliary gear group connected in series with the main gear group. The auxiliary gear group was provided with a range of speed change ratios substantially equal to, and preferably slightly greater than, the range of speed ratios included Within a selected portion of the main gear group. Disclosed with 'said two gear groups in said application was semi-automactic means actuable at the will of an operator for shifting said auxiliary gear group when the main gear group is in neutral position.

Through this arrangement, it is possible to shift the main and auxiliary gear groups from low position to high position, or vice versa, passing twice through the entire range of said selected portion of said main gear group with only one simultaneous shift of the gears in both gear groups. In this way it is possible to provide a multiple speed transmission assembly having a larger number of shift ratios than can be conveniently provided in a single unit transmission, while avoiding a complex shift pattern in which several simultaneous shifts of both the main and auxiliary `gear groups are required. Previously it Was common in multiple speed transmissions, having a main gear group or transmission with normally spaced speed ratios and a serially connected auxiliary gear group or transmission for splitting the ratios in the main transmission, to have each gear group operated With a separate shift lever, all as set forth and explained in detail in said application, Serial No. 133,404.

In the specific embodiment disclosed in said application, a fluid actuated mechanism was utilized with the interlock mechanism of the main gear group for actuating the auxiliary gear group. It is the purpose of this invention to disclose and claim a different structure involving an electrically operated mechanism, also associated with the interlock mechanism of the main transmission, for carrying out the same broad purposes as those effected by the said hydraulic mechanism and for securing certain operating characteristics not present in the specific embodiments previously disclosed.

Accordingly, one ofthe broad objects of this invention is to provide a multiple speed transmission assembly, Vincluding main and auxiliary sections connected in series, whch can be shifted through its entire range by manually actuating only one shift lever.

A further object of the invention is to provide a multiple speed transmission assembly, as aforesaid, which can be so shifted throughout its entire range with one hand and which can be so shifted easily and conveniently.

A further object of the invention is to provide a multiple speed transmission assembly, as aforesaid, wherein the shift of the auxiliary gear group during said simultaneous shift may be performed easily by semi-automatic means at the Will of an operator when, but only when, the associated main gear group is in neutral position.

A further object of the invention is to provide a multiple speed transmission assembly, as aforesaid, in which the pressure effecting shifting of the auxiliary gear group is held continuously effective on the auxiliary shifting means in either shifted position thereof.

A further object of the invention is to provide a multiple speed transmission assembly, Vas aforesaid, in which the means controlling the shifting of the auxiliary gear group are wholly independent of the pressure fluid supply thereto.

A further object of the invention is to provide a multiple speed transmission assembly, as aforesaid, having means preselectable at the Will of an operator which will automatically shift said auxiliary gear group when, but only when, the shift rods of the main gear group next after such preselection enter into the position corresponding to Y the neutral position of said gear group.

A further object of this invention is to pro-vide a mechanism for effecting a shift operation, as aforesaid, which mechanism is simple in construction, easy and economical to fabricate and requires a minimum of maintenance.

A further object of this invention is to provide a mechanism, as aforesaid, which is sufficiently fiexible to permit its installation in substantially any conventional type of truck, tractor or similar heavy duty vehicle.

A further object of this invention is to provide a device by which the shifting of the auxiliary gear group in an assembly, as aforesaid, may after preselection by an operator, be automatica-lly effected by electrically actuated control mechanism immediately upon entry of the main gear group into neutral position.

A further object of this invention is to provide control mechanism, as aforesaid, actuable by an bodying the invention with the shiftrods and` interlock mechanism in one of their two normal positions and with the sectional portiontakenpn line I-I of Figure 3.

Figure 2 is a fragmentary view of Figure 1r showing the shift rods and the interlock mechanism in theirother position.

Figure 3 is a central cross sectional view of a transmission assembly, to which thisinvention relates, taken along asubstantiallyvertical plane through the axes of the main shafts of the main and auxiliary boxes andl indicated by the line III- III in Figure 4.

Figure 4 is a sectional view ofthe main gearV box taken along the line IV-IVofFigure 3.V

Figure 5 is a sectional view of said transmission assembly taken substantially along the line V-V of Figure 4 and showing a portion of the main box output shaft in brokenlines.

Figure 6 is a fragmentary view of theshift rods in their neutral position and further showing the interlock mechanism.

Construction z'11.`gc11.eallA The structure` in general comprises fluid (as air) energized actuating means for effecting a shift of the auxiliary gear group, and electrical means operatedpby the interlockmechanism of the main transmission for Acontrolling said fluid energized actuating means.

More specically, the fluid. energized actuating portion4 of the device includes a shift fork connected to the auxiliary gear groupa fluidpressure cylinder for actuatingA the shift fork, a source of uid under pressure and a valve, responsive to a pair of solenoids, for controlling the flow of said fluid from a source to one end, or theother end, of the cylinder. Y

The electrical control portion ofithe device comprises a series circuit having a pair of branches, each branch havingA a solenoid for moving said valveinto one of its operating positions, a manually controlled selector switch for selecting which of said branches is connected to the remainder of said circuit, asource of,V constant potential and a control switchv actuated by the interlock mechanism of the main transmission for energizing or de-energizingrthe vselected one of said solenoids.

Said control ,switch` is normally closed, and so held by a yieldable means, as a spring, and is opened, overpoweringsaid spring, bymovement of said interlock mechanism, asthe `gears associated therewithvare movedout of` neutral position. Whenever the main gear group is in a.Y

shifted position the control switch is .held open by means actuated by said interlock mechanism, and as soon as the main gear group. returns to neutral position said control switch is` permitted to close. When the control switch closes, one

solenoid or the other is. energized, depending upon.

.the position of the selector switch. Thus energized, the solenoids will either move the valve into its other position, or hold it in its present position. Thus, said valve, if held in the same position, will continue to direct fluid under pressure into a cylinder in the same direction as previously and the Vshift fork of the auxiliary transmission connected for operation by said cylinder, will not move. On the other hand, if the solenoid core moves, it shifts the valve into its other position whereby the pressure fluid will be directed into. the opposite end of the cylinder and the shift fork will be actuated to effect a shift of the auxiliary gear group.

Thus, so long as. the selector switch is not moved, the main gear group can move into and out of its neutral position freely without effecting a Vshift of the auxiliary gear group. However, when the selector switch is moved, it will effect such preselection of the control mechanism that, upon the next entry. 0f the main scar sroilpillio neutral position, a shift in the auxiliary gear group will beA broughtabout.

Construction in detail- In the speciiic embodiment of. the. inventionherein disclosed, there is provided a main transmission or box 1D, containing almain gear 'group'. A

which is associated at one end-with an auxiliary transmission or box il, containing an auxiliary'.

gear group in. series connection witliftheY main gear group. The other end of the main box fill' is associated with an input shaft. l5 covnfnectible with the clutch of a vehicle (not shown). An output shaft 54 extends from the auxiliary` box lifor connection to a propeller shaft in a' conventional manner. Said gear groups ,are here` shown in two separate,l connected Yhousings for. convenience in reference butthey may both be* enclosed in arsingle housing ifvdesired` without.,

going outside the scope of4 thisinvenftion The auxiliaryrgear group is provided with synchronizers l5 and 66, preferably of the vfriction clutch type.

Although the present invention is not concerned with the details of either the main gearv group or the auxiliary gear' group, but rather lies in the association and co-action of said-gear groups with eachother and with theA controlv means herein disclosed,4 the following description of saidv gear groupsis given by way olf` example but should .be recognized as an exanfipleonly.andv

not limiting.

The4 mais bow mean leftwardly and rightwardly with respect to l thetrans'mission assembly when POStOned as appearing in Figure l. The terms ir1wardly and outwardlyshall be understood to have reference to the geometric center of the transmission assenlbly or the sections Il), l and I2, thereof. The terms upper or upWa-rdlyf and lower or downwardly shall be understood to*V refer tothe entire assembly when positioned and/or operat- 5 ing inits normal manner. of use` The term-one step or one-half step, when used with reference to the spacing of gear ratios, connotes the ratio spacing of the usual five-speed transmissions wherein the five speeds extend from lo-W through high to overdrive and each ratio` change constitutes one stepf In certain common transmissions now on the market, the adjacent gear sets have percentage steps from one to the next from about 60% to about 90%, but this is illustrative only and not limiting.

With specific reference now -to the main box here selected for illustrative purposes, the main transmission box I is provided with a centrally disposed main shaft I4 and an input shaft I5, which shafts are preferably c'o-axial, With their adjacent ends closely spaced from each other Within the main transmission section I3. The main shaft Id is rotatably supported upon the main bearings I6, Ia and I6b within the main box I and the pilot bearing I1, said pilot bearing being mounted in and upon'the adjacent end of the input shaft I5. The input shaft I5 is rotatably supported in one end of the main box I6 by means of the main bearing I8. The leftward end of the input shaft I5 is splined for conventional coupling usually -through a clutch with said power means and issupported by a clutch pilot bearing (not shown).

The leftward end of the main shaft I4 is splined for axially movable support of the clutch member 23 having leftward and rightward sets of external teeth 24 and 25, respectively. The clutch member 23 is provided With a circumferential groove 26 between said teeth for engagement by a clutch fork 21, which fork is actuable by a shift lever 22 in a conventional manner.

The rightward end of the input shaft I5 is provided With an input gear 28 having internal and external teeth 29 and 3|, respectively. The internal teeth 29 of the input gear 28 are engagable by the leftward teeth 24 of the clutch member 23 when said clutch member is in its left- Ward position upon the splined portion of the main shaft I4.

A small floating, low speed, gear 32 which is rotatably supported upon the main shaft I4 adjacent to the clutch member 23, is provided With external teeth 34 and internal teeth 33 selectively engagable by the rightward teeth 25 of said clutch member 23.

A medium iioating, second speed gear 35 is rotatably supported upon the main shaft I4 adjacent to the rightward side of said fioating gear 32 and is provided with clutch teeth 36. A shaft gear 31 is positioned adjacent to said clutch teeth 36. A ring gear 38, having external teeth 39, is provided with internal teeth 4I whereby said ring gear is supported upon and engaged by the shaft gear 31 and is axially movable leftwardly and rightwardly with respect thereto. The ring gear 38 is provided with a circumferential groove 42 engagable by a clutch fork 43 which clutch fork is actuable by means of the shift lever 22 in a conventional manner.

A large floating, third speed, gear 44, having clutching teeth 45, is rotatably supported upon the main shaft I4 adjacent to the rightward side of the shaft gear 31.

The rightward end 46 of the main shaft I4 is splined in a conventional manner and extends through the rightward end of the main box I0 into the auxiliary box II. A second ring, overdrive gear 41 has an internally splined, centrally disposed, opening for support upon and engagement with the splined rightward end of the'main shaft I4, and is' disposed adjacent to the rightward side of the main bearing I6.

A` main output gear 48 having external teeth 49, internal teeth 5I and being Within the auxiiliary transmission box I I, is provided with a hub 52 which is internally splined for engagement with the rightward end 46 of the main shaft I4. The main bearings I6a and I6b encircle the hub 52 for support thereof. A pilot bearing 53 is mounted substantially within the rightward side of the output gear 48 for rotatable support of the leftward end of the auxiliary main shaft 54 hereinafter described. j

A main countershaft 55 is rotatably supported within the main box III, preferably directly below the main shaft I4 and parallel therewith, by the bearings 56 and 56a. A spur gear 51 is secured to the counter shaft 55 adjacent to the bearing 56 for continuous engagement with the external teeth 3| of the input gear 28. A small spur gear j 58 is secured to the countershaft 55 adjacent to the rightward side of said gear 51. A medium spur gear 59 is secured to the countershaft 55 adjacent to the rightward side of the small spur gear 58 for continuous engagement with the external teeth 34 of the small floating, low speed, gear 32. A large gear 6I is on the countershaft 55 in continuous engagement with the medium oating, second speed gear 35.

A small countershaft gear 62 is spaced rightwardly from the large countershaft gear 6I and is continuously engageable with the large floating, third speedv gear 44.

A countershaft floating gear 63, having external teeth 64 and internal teeth 65, is rotatably supported upon the countershaft 55 adjacent to the rightward side of the bearing 56a.

The rightward end of the countershaft 55 is splined in a conventional manner. A clutch member 66, having a circumferential groove 61, is provided with an internally splined, centrally disposed opening for axially slidable support of the member upon the splined rightward end of the countershaft 55. The clutch member 66,

`which is adjacent to the floating gear 63, has external teeth engagable by the internal teeth 65 of the said fioating gear 63. The circumferential groove 61 is engaged by a clutch fork 68 which is actuable by the shift lever 22 in a conventional manner. The external teeth 64 of the iioating gear 63 are continuously engagable by and with the second ring, or overdrive, gear 41,

A reverse idler shaft 69, `(Figure 5) is secured Within the main transmission box I6, is disposed parallel with the countershaft 55, and is spaced substantially horizontally therefrom. Since it is provided With conventional gearing and operated in a conventional manner, detailed description thereof is considered unnecessary and is accordingly omitted.

The auxiliary boa:

- mally equal to the entire range of the main box,

including overdrive, plus about one half step. Alternatively,'however, the auxiliary box ratios may differ by an amount equal to, or a little greater than, some-i other j selected; porti'on-l oflzthev main;

splining.

The clutchsleeve 8i i is :provided: withleftward: and rightward ringsfofiexternal teeth 82.@` and, 83; respectively, adjacent tofy the axial; faces;` thereof; anda circumferential; groovef rois dis-f posedintermediate'. the .rings of: teeth: Thegcirf 20 cumferential groove 34Y is;A engaged: by-ax clutchi fork; secured'to a semi-automatic shiftmgdevice, hereinafter describedin" detail, for reciprocable` movement of the clutchs1eeve:8ionthe. auxiliary shaft 54;` The leftwardzteeth 82'ofthe*v clutch sleeve 8l z are 'controllablyI engagable` Withl the internal teeth' ly oftheV main output gear 48,1. such: control .being` eiected-f by the.synchronizing;r clutch 19 when the clutchzsleeve 8lI moved! leftwardlyalong theauxiliaryfmain:shaftk- An auxiliary output gear` which is rotatably sup.-v ported uponV .the auxiliary mainwshaft; 54A adjaf Y cent to the rightward sideof clutch.-sleevek 81; provided with.` internal. teeth` 811 and. external teeth;88. The rightwardringgof teeth-T83:onthev 35A clutch. sleeve.` 8.! is. controllably; engagable: With| the internal teeth 81gof the outputgear-:86, said control being eiected by the;synchronizingclutch Bwhen the clutch sleeve 8 iv is moved rightwardly along the auxiliary main shaft 54;- 40A The synchronizing clutches Maand. 8U-, maybe.- of' anyA convenient and. conventional. type; suchf as. the.: cone. clutch disclosedf and:. iesoribed` in: Patent: No; 2,468,155; Hence,. detailedgdescrip-r tiorrthereof iszomittedhere.

It will be unclerstoodthattha capacity:oithese'f-v synohronizersfor :best results; willbesucienti to effect substantial.synchronization,duringhe.. timeitheshift leverA isrpassing through; neutral position ata. relatively rapidzrata:` andipreferablyv' 50 during thea firstw half' of: such. passage:A having ini mind that the entire, shift' Will; normallyv takef about 8.6 second onzanupshift and about-"1.8

seconds'ona downshift;. Thus; substantial syn-- chronization. will preferably bef completed: lessf than 0.5 second and .to accomplish `thisfthe syn@ chronizers` must' be. oi; relativelylargef capacity.` Nevertheless, successfulV operation will bef se-L cured if` there.r is onlya sufcientfapproximation of synchronization in the auxiliary7 boxrto'permitlA prompt shifting of the main box and actual shifting of the auxiliary will in-somefinstances actually be completed after the main box has been shifted.

An auxiliary countershaftz fCFgure- 3) which is preferably parallel with the" auxiliary main" shaft 54 and'spacedl downwardly therefrom;- is rotatably supported at its'extremities-'withinthe' auxiliary box Il'bytheebearings-93and^93a-y A large geartis supported upon the auxiliary countershaft: 92 near its leftwa-rdend'for rota'- tion therewithL and continuous engagement withA the .external teeth" iiliofrthemain 'outputgear- 48'; A' pinion gear:95E-supportedupon'theauxiliary countershaftlBZrnearrits rightwardiend forv rotation therewith and: continuous.-engagement;A with: the external teeth;.88 of theauxiliaryy out putzgeaif.

Thus; inthis. embodiment', the auxiliary box H is' provided with gears'. effecting a direct.. drivel and onereductionratio. The difference between".

thedirectdrive and reductionratios ofthe auxiliary boxin this embodiment of the inventionA is approximately one half step greater than the.- entire speed range betweenii'rst and ifthvgearratios provided in the main box-l 0.

Thefollowingtable disclosesin detail thegear` ratiosxuse/d in this'embodimentand'which have been found to operate satisfactorilyfin the maini transmission box'of a unitand auxiliary trans-- mission assembly? of an otherwise conventionall truck:

A Prtcent. 6D. Gear Tesltlonu. gr Between;

Adjacent Sets" 2:10 2S l. 64 29,5'. Third. 1.27v 27. Fourth (direct) 1. 00 28" Fifth (overdrive).y 0. 779

The'y reduction2 drive) gear'- ratio f in"v the auxiliary box; for useiwitltthe vabove ratiosfinfthe main` box, Was'fundtobeisatisfactoryl at 3:55. Thus,-

the ratios providedE inir the main' boxJ are sub-- stantis'rllyv equal; approximately'halfstep', ratios;v as-ihalfiste.p" is' denedlab'ove. Theratio pro-1 vided' in tha' auxiliary-"box when in"reduction position spans -the--entire1main box'Y ratios (2.'69*

in the example above) plus-aboutfone half-step (in this ease =32 percent) a It willi be Vunderstood that the. abovedescrip,-y

tion of the maintransmissionbox-lf'andthe auxiliary` transmission box Hiistgiveninv detail for. illustrative purposes, `only, .andit is. notA in.-

tended. that' the. specific. details;-thereofr impose. any limitation. upon the.. scope. .of the; invention..A

Auaziiary :bor actuan'ng.-y means.

The means for actuating'the. auxiliary b'ox'may bev any of a wide variety of power' devicesto move.

the slfriftable'member'oiV the auxiliary box, When,..

andv only when, theoperator movesa suitable' preselecting"devicen and theunainbox thereafter comes into neutral position: The operating partey may;VV be" placed anywherey Which is`. oon-.-v

venient and; consistentwith: their effective op.- eration: The' specific devicev hereinafter described will illustrate. one eieetive.embodiment.v

As'showninliligure'; the auxiliary box actuatingsectionA i 2 'is preferablymounted on, or, adjacent to, the. auxiliary transmissionbox ll for.

semiautoxnatio actuation of theauxiliary clutch, The actuating section.` l2..contains an.. automatic. shift control mechanism -99. (Figures.

l andS) comprising a double acting actuating Y means, such as the cylinder |05, an actuation arm |00, and a twoway selector valve |02 of any conventional type,

' which is connected in a conventional manner by means of pipes |03 and |04 to said cylinder |0|. Although the cylinder is hereinafter described and disclosed as an air cylinder, which may be either pressure or vacuum, it will be understood that said cylinder may also be actuated hydraulically. A vacuum system is hereinafter assumed for illustrative purposes.

The selector valve |02 is in turn connected to a vacuum tank |03, by means of the pipe |09. The vacuum in the tank |08 may be maintained therein by the engine manifold, not shown, through the pipe which communicates with the tank |08. A check valve |50 may be placed in the pipe to retain the vacuum in tank |08 when the manifold pressure rises.

The selector valve |02 is actuated by the plunger |3| of the solenoid, said solenoid having independent windings |32 and |33. Said valve |02 is of the conventional type wherein the parts thereof are so proportioned that when said valve is fully moved into either position, continued pressure on the inlet side thereof will tend to hold said Valve structure in whichever position it then occupies. Thus, regardless of which way the valve is shifted, continued suction from the vacuum tank |08 will tend to hold the valve in that shifted position.

Said plunger |3| is operatively associated with the solenoid windings |32, and I 33 in such a manner that the energization of the winding |32 will move said plunger |3| rightwardly, as appearing in the drawing, and energization of the winding |33 will move said plunger |3| leftwardly, whereby corresponding movement of the mechanism of said valve |02 is brought about. Said solenoid is of any conventional type and, in the particular circuit here utilized to illustrate the invention, each winding thereof is connected through a manually controlled, conventional selector switch |34 to a series circuit |35 which includes, in addition to the selector switch |34, the normally closed control switch |36 and a source |31 of constant potential. The selector switch |34 is manually actuated by any conventional means under the direct control of the operator, such as a selector lever |38 mechanically connected to said switch |34 by a rod |39, and which operates to determine which of said solenoid windings is at a given moment connected to the source |31.

The shift rods H4, H5, H6, and ||1 and the interlock means i i3 associated therewith may be of conventional form, such as those illustrated in said application Serial No. 33,404 or as further illustrated in detail in the United States Patent to Padgett No. 1,943,694. Said shift rods are conventionally and reciprocably supported in guide block l2?, located within .he housing of the main box lo, as shown in Figures 3 and 6. Each shift rod has an annular groove H9 (Figures 2 and 6), which grooves are aligned with respect to each other in a direction perpendicular to the axes of said shift rods when said main gear group is in neutral position. The openings |26 (Figure 2) which extend through the shift rods |41, H and I6, communicate with diametrically opposite portions of theV grooves H3. Pins |2| are slidably disposed within each opening |20 and balls |23, |24 and |25 are disposed between the shift rods and engageable by the pins |2|. Each ball is substantially equal in diameter to the distance between the shift rods passageway |26 is provided in the guide block |21 transversely of the shift rods for preventing movement of the balls out of their alignment with each other when one of the shift rods, together with the pins |2| therein, is moved during a shift of the main box. There are as many balls as shift rods, with one ball |22 disposed laterally outwardly of and adjacent to the shift rod H4.

The several balls and pins |2| cooperate with the grooves ||9 to provide an interlock mechanism which prevents more than one shift rod from leaving neutral position at any one time.

When one of the shift rods, here for illustration the rod ||0, isl shifted out of neutral position (Figure 1), the balls, the pins and the rod ||6 cooperate to urge the actuating pin |01 rightwardly, as appearing in Figure 1, against the compression of the spring lilla to open the control switch |36, which is preferably a toggle type of micro-switch. l

When the shift rods are all in neutral (Figure 2), the spring lilla moves the actuating pin |01 leftwardly away from the control switch |36, whereby said switch is closed, thereby energizing the circuit |35 and whichever, solenoid winding is connected therewith.

Operation Inasmuch as the particular main gear group and auxiliary gear group above described are conventional, vtheir operation will be understood without description. However, reference may, if desired, be made to said applicationserial No. 133,404 for a detailed, description of the operation of this particular main and auxiliary gear assembly.

The interengagement of the various corresponding gears within the transmission assembly |3, for the purpose of effecting the various above mentioned' gear ratios, may be accomplished in a conventional manner by means of the shift `lever 22 and the shift rods IM, |15, ||6 and ||1.

The clutch sleeve 8| in the auxiliary box is moved axiallyalong the auxiliary main shaft 54 (Figure 3) by means of the actuating arm 100 of the air cylinder |0| acting through the clutch fork 85. When the clutch sleeve 8| is in the leftward position it engages the output geared, thereby effecting a direct drive through the auxiliary box When the clutch gear 8| is in the rightward position (Figure 3), it engages the auxiliary output gear B6, thereby eecting a re-V duction drive through the auxiliary boxi The synchronizing clutches 19 and 00 provide means for reducing the speed of the main shaft il! prior to engagement between the clutch sleeve 3| and the main output gear 40, in a conventional manner, and for speeding up the main shaft i4 and auxiliary countershaft 92 prior to engagement between the clutchl sleeve 8| and the auxiliary output gear 86, also in a conventional manner.

Turning now to the operation of the shift conl speed of the power means driving the entire transmission assembly `has retarded beyond the point at which engagement of the gears inthe QKLEMBQB gnew shift position-may be made. Since rthis normally requires less a;-second,.thcneedffor rapid s hii t v is-zapparent.

Thus, the shift ,fork 15, 4when positioned :as appearing. in rsolid. lines ,(Figure l) ,ff'eiccts fafreduction drive ,through the-.gears inftheauxiliary box 2 and, vwhen positioned as appearing prohenlines l{ligure rllsaidork effectsfazdirect drive through` said v auxiliary hox. ,It .will :be-ias- ;sumed Y for descriptive `:purposes fthat :movement Mof the plunger |-f3g| deitwardly J-wil1;direct pressure :luidjnto the ,leftward Vfend of the cylinder L I and movement-:of saidplunger |3| rightward- `ily `will direct pressure fluid into :the riehtward end of said cylinder It will --also beiassumed thatyow-orfiuidinto 'the leftvvard end ofthe icylinder will move the V,shift `:fork ,85 :into its Vrightward, :or .gear reduction, positiongandflow of'pressure iiuidzinto the rightwardgendgof cylinder i||`|| will move-'said shift ifork `85 .into its leftward, or direct drive, .posi-tion. rlhese ,assumptions are :all :consistent vwith :a preferred embodiment of the apparatus fout fare here rdesignated for 'illustrative purposes 10.11151. ltwillbe evident .that :they/may ,bezaltered without destroying the -purposes or scope tof :the invention.

Thereforein starting :a Vvehicle equipped with vthe improved :transmission of this invention iin its lowest gear, the selector -lever |38 wiil #be l"in its downward position `and'solenoid winding |32 will Vlee connected to thesource |31, thevalve 5F62 will be so positioned that pressure fluid-will be introduced into the leftward end of the cylinder lel and the shift fork'85 willbe in its rightward position.

As rthe vehicle gat-hersspeedand thegears in the main gear group are shifted `frornthe vlowest ratio to the 'highest ratio .in ,conventionalmanner by the operation of the :shift 'lever i2, the control switch |36 is .closedveach time themain gear group, and consequently the interlock mechanism, comes into its neutral position. This lcloses the circuit but, since.such closing still energizes only the winding "|32, fthe energization of circuit Y|35 effects no change -in position of .the :solenoid plunger 3| 4and consequently -no Lchange inthe position vof the valve 1,02. Thuspthe pres- Vsure'iiuid continues constantly to vbe directed 'to the-leftward end offthe Acylirideri 0f| and the shift l fork '85 continues to be held its rightward, or reduction, position under v the constant suction within the vacuum source |08.

However, if upon reaching the end of the available -ratios in the main Igear group wthe `,operator desires to shift Athe auxiliary :gear lgroup into Yits direct drive position and to return the main gear group to its lowest ratio in order -to continue the progression of the entire transmission unit through its several ratios,the selector "lever |38 is moved into its upward position while the main gear group is still in a shifted position. This -will place the apparatus'in the position shown in Figure l, wherein said selector lever Pis its upward position -hut the shift fork `85 'is still in'its rightward, or reduction, position'.

`When the mai-n transmission Ynowmoves into its neutral position, and the bal-ls fall-into the several Vrod grooves (Figure 2), the control switch |36v closes and the circuit |315 is energized. Because the selector switch 34 now connects Athe -solenoid winding |33 to the source |31, in place of the solenoid winding |32 `formerly connected, Vthe closing of the control switch |36 now energizes the said solenoid winding |33 and .causes the plunger Cai i12 |13| to :move zrigntwardly. lthis position the :valve :t-idi'rectszpressure fluid into the` rightward zend of the cylinder |;|1| and'zthe shift fork 85 :is .movediinea leftwardnirection.

zrst -.reaction .to movement `ci? the f clutch sleeve iiLleftwa-rdly: is a, synchronization oiits .1ro-

Y tational-speedwiththespeed of thernainroutput geare' by meansof thesynchronizing clutch .19. AWhen this synchronization has been :accomplished, the clutchsleeve-.S under thecontinuing urging pf :the pressure -fluid, `shifts 'the auxiliary zbcxromreduction to directdri-ve. .Themain box l0 -can (be shifted by means .of the shift lever '22 ,zintotsflow geanpositionas soon as saidsyn- .ohronism feected, whether -.or v.not the clutch l sleeve SI yhas actually completed its shift. .Ac-

eordingly, -the shift lever -22 :is simultaneously moved from its high position tofits -low position fand the Ishift -i-rom direct drive in ,the :main box ,and v:reduction idriveV .in the auxiliary box to .low Lratio Lin ithe :main fbox and :direct .drivein .the auxiliary :hoxis .completed rEhe shift progressionzmaygthen hepcontinuedfin .the main boxras .desired -and in A,a ,conventionalzmannen :Downshiftingoi theztransmission is carriedout ,in :the same manner as described -aboveior flip- ,shifting excepting -only that the `motions areiin .the reverse direction.

-lt 4will he observedthat when'the :auxiliary gear group has once shifted as aresultofamovernent 'of .the .selectorlever L36 followed .by'entry of the .main Igear .group `into neutral, 4the `main gear group may thereafter-enter and leave .neutral as .often as .desired without eiecting any further .shift .of vthe .auxiliary gear group. Likewise, it ,will he observed that so ,long as the main gear ,group .does notenterinto -its neutral position, lthe selector .lever :|318 maybe moved upwardly or .downwardlygas often as desired withoutfeifecting any ,ch-ange inthe auxiliary Agear Ygroup. Shift- .ing .of the auxiliary Lgear group is, therefore, ei- Afooted .only by. a :movement of .the lever 1.3.3 from .one position into its .other position followed by vmovement...of .the main gear group :into neutral position.

.Inasmuch as thepr-,essureuid :is at all times .eiective on .the cylinder lil., (1) there .is practically A.no 4chance that the vauxiliary gears will V.come .out of -either shifted position accidentalh vand .(2) Y the,continuation of this pressure even after completion 4of the shift `in-the main gear group .maliesit possible for the shift in the 'main gear group to be completed iirst andthe shift inthe Yauxiliary geargroup may then follow as soon as the synchronizing mechanism therein permits.

vPersons familiar with this general type of equipment will also recognize that by having the vfluid pressure continuously effective in said cylinder, it will be possible during a shifting operation .momentarily Vto reengage the clutch and simultaneously either increase or decrease the :speed of the engine for lip-shift or down-shifting, respectively, and thereby assist the auxiliary-gear group to complete its shift.

vIt will also be recognized that the provision'of the electrical control means .for determining the flow of pressure fluid willconstitute a positive and reliable apparatus, one not readily subject `toirnproper operation and means wholly independent of the pressure fluid system.

It will be noted that since the main gear group will normally be in gear during operation of the transmission, and accordingly one of the shift rods will be out oi neutral position, the circuit l 35 will he broken Vby the .control switch-[Sil during a majority of the time and, therefore, the power source |31 will not be unreasonably depleted. When the vehicle with which the above described control mechanism is used is not in operation, the circuit |35 may be broken by the ignition key of said vehicle or by other conventional means arranged in a conventional manner.

Although the above mentioned drawing and description apply to one particular preferred embodiment of my invention, it is not my intention, implied or otherwise, to eliminate other variations or modications which do not depart from `the scope of the invention unless specifically stated to the contrary in the hereinafter appended claims.

I claim:

l. In a multiple speed transmission, the combination comprising: a first gear group having shift rods and an interlock mechanism associated therewith, and a second gear group having friction clutch synchronizing means and means serially connecting said second group with said rst group, said second gear group having a ratio not materially less than the ratio in the rst gear group between its low position and its direct drive position; shifting means automatically actuable upon entry of said first gear group into neutral position for initiating engagement of said synchronizing means and eifecting shifting of said second gear group, said shifting means including power means effecting engagement of said synchronizing means and effecting the shifting of said second gear group upon substantial completion of synchronization; energizing means comprising an electric circuit for effecting energization of said power means; control means operable to open said circuit; and actuating means associated with, and operable by, said interlock mechanism for operating said control means, and thereby opening said circuit, when said rst gear group is in a shifted position, means causing said circuit to close immediately upon the entry of said rst gear group into neutral position.

2. In a multip-le speed transmission having a main gear group and an auxiliary gear group in series therewith, said second gear group having a ratio not materially less than the ratio in the first gear group between its low position and its direct drive positionV the combination comprising: a plurality oi shift rods for effecting a shift of the main gear group and an interlock mechanism associated with said shift rods; friction clutch synchronizing means associated with said auxiliary gear group; a source of fluid under pressure; fluid actuated means connected to said source and shift means operable thereby for automatically initiating said synchronizing means and shifting said auxiliary gear group; a source of electric energy and a control switch and means actuated by said interlock mechanism for opening said control switch when said main gear group is in gear; a manually controllable selector switch and means connecting said source of electric energy, said control switch and said selector switch in series circuit; and an electrically responsive two-position valve having a pair of solenoid windings, said windings being alternatively connected through said selector switch to said series circuit for controlling the direction of actuation of said fluid actuated means; means operable from said interlock mechanism for closing said control switch when main gear group is in neutral, whereby said valve is moved from one position to the other or held in a selected position depending upon the position -of said selector switch.

3. In a transmission assembly having a main gear group, an auxiliary gear group, said second gear group having a ratio not materally less than the ratio in the first gear group between its low position and its direct drive position and a plurality of shift rods for said main gear group and an interlock mechanism associated therewith, a shift control for the auxiliary gear group comprising in combination: a source of fluid under pressure and a fluid driven actuator connected thereto; shift means connected to said actuator for shifting said auxiliary gear group; a twoposition valve controlling the direction of flow of fluid to said actuator; electrically responsive means controlling the position of said valve and a source -ofelectric power for energizing same; a manually controllable selector switch controlling the flow of energy from said power source to said electrically responsive means for urging said valve into one position or the other position, and a normally closed control lswitch in series with said power source and said selector switch; actuating means associated with said interlock mechanism for holding said control switch open whenever said main gear group is out of neutral position.

4. A devicefor shifting an auxiliary gear group having a shift fork and being in series association with a main gear group, said second gear group having a ratio not materially less than the ratio in the first gear group between its low position and its direct drive position, said main gear group having a plurality of parallel, spaced shift rods and an interlock mechanism comprising a circumferential groove on each of the shift rods, a ball positioned between each of said shift rods and disposable within said grooves, and co-axial pins slidably extending through said shift rods in communication with said grooves, said grooves, balls and pins benig on a common axis perpendicular to the axes of said shift rods when said main gear group is in neutral position, the combination comprising: a fluid responsive actuating cylinder and means operatively connecting the piston thereof to said shift fork; a source of fluid under pressure and conduits connecting same to each endv of said cylinder; a two-position valve interposed in said conduits; a two-winding solenoid having an axially reciprocable plunger connected to said valve for moving same in response to the movement of said plunger; a source of electric power, al microswitch and a selector switch and means connecting said three lastm named elements and the solenoid windings in a branched series circuit wherein said windings are in parallel with each other and the position of said selector switch determines which of said windings is connected with the other elements of said circuit; manually actuable means for operating said selector switch; an actuating pin coaxial with the assembly of said balls and pins and means supporting said actuating pin for axial movement thereof; a further ball snugly disposed between said actuating pin and the adjacent shift rod andengageable by the pin therein; resilient means urging said actuating pin toward said shift rods, means supporting said micro-switch for actuating and opening by said actuating pin when said main gear group is in gear and for closing said micro-switch when said main gear group is in neutral.

5. In a multiple speed transmission, the com .bination comprising: a first geargroup having shift rods and a second gear group having fric-y tion clutch synchronizing means and means annees "serially connecting said second group with'said first group,saidsecondfgear-group-having a. ratio not materially less than the'ratioin the first-gear ygroup between its low positionand its direct drive position; shifting means automaticallyactuable upon ventry of said first gear group into neutral position for initiating engagement of said synchronizing means and effecting shifting of said second gear group, said shifting means including power means effecting engagement `of said synchronizing means and effecting the shift-ing of Isaid second gear group upon substantial completion of synchronization; energizing means comprising fan electric Ycircuit Vfor leffecting enerfg-ization of -said power means; cont-rolmeans operable to open said circuit; and actuating vmeans Vassociated with, and operable by, said shift rods for operating said cont-rol means, and thereby "opening said 'circuit Yin `a Vshifted position Vand 'causing said circ-uit `to close immediately upon the -entry fof said -iirst gear g-roup into neutral position. Y

Y, ein a multiple speed transmission, the comb ination comprising: a first gear -group having shift -rods and -a second gear group having friotion clutch synchronizing means and means seri- -aily connecting said second group with said first group, said second gear group having a ratio not materially less than the ratio in a selected portion -of the Viirst gear group; shifting means automativ v cal-ly actuable `upon entry of said rst gear group into `neutral position for initiating engagement of `said synchronizing means and effecting shifting of said second gear group, said shifting means including power 'means effecting vengagement of said Ksynchronizing means and effecting the shifting of said second gear group upon substantial completion of synchronization; energizing means comprising an electric circuit for effecting energization of said power means, said circuit includ- 'ging a manually operable 'selector switch for conwith said iirst group, said second gear group hav- 1 ing a ratio not materially less than the ratio 'in a selected `portion'of the rst'gear group; shifting means automatically 'actuable upon entry of said first gear group into neutral position for initiating engagement of saidsynchronizing means and effecting shifting of said second gear group, said shifting means including power means effecting engagement of said synchronizing means and effecting the shifting of said second -gear group upon substantial completion ofsynchronization, energizing means comprising an electric circuit lfor effecting energization of said power means, said circuit including a manually operable selector switch for controlling the direction of operation of said power means; control means operable to Vopen said circuit, and actuating means associated with, and operable by, saidmanually shift- 'ablemeans for operating said control means, and thereby opening said circuit in a shifted position -and'causingsaid circuit to close immediately upon the entry of said -rst gear-group into neutral position.

8. -Inamultiple speed transmission, `the combination comprising: a first gear group having shift -rods and asecond gear group having frictionally actuated synchronizing means and means serially connecting said ysecond group with said first group, said second gear group having a ratio not materially less -thanthe ratio in a selected portion of the first gear group; shifting means automatically actuable upon entry of said first gear group 'into neutral position for initiating engagement of said synchronizingmeans and eiecting shifting of said second gear group, said shifting means including vpower means effecting engagement of `said synchronizing means and effecting the shiftving of said second gear group upon substantial completion of synchronization; energizing means comprising an electric circuit for effecting ener- `gization of said power means, said circuitinclud- -ing amanually operable selector switch and a normally open control switch; an electrically responsive two position valve energized by said cir- `cuit to occupy one position or the other according to the position of said selector switch and connected to said power means for controlling the -direction of operation of said shifting means; control means operable from said shift rods for closing said control switch immediately upon the entry of said first gear group into neutral position.

9. In a multiple speed transmission, the combination comprising: a first gear group having manually shiftable means and a second gear group Vhaving frictionally actuated synchronizing -means and means serially connecting said second group with said iirst group, said second gear group having a Vratio not materially less than the ratio in a Aselected -portion ofthe rst gear group; shifting means automatically actuable upon entry of said first gear group into neutral position for initiating engagement of said synchronizing means and effecting shifting `of said second gear group, said Yshifting means including powerrmeans effecting 'engagement of said synchronizing means and effecting the shifting of said second gear group upon substantial completion of synchronization; energizing means comprising an electric circuit 'for effecting energization of said power means, said 'circuit including a manually operable selector switch and a normally open control switch; an electrically 4responsive two position valve en- "ergized by said circuit to occupy one position or the other according to the position of said selector switch and connected to said power means for controlling the direction of operation of said shifting means; control means operablefrom said manually shiftable means lfor closing said control switch immediately upon the entry of said first gear group-into neutral position.

CHARLES 'PERKiNs kRefi-rentas cited in the sie of this patent UNITED STATES PA'IEN'rs Y Hukiu sept. 12, o 

